Feeding head for shaker or jigging conveyers



Jan. 26, 1937. l.. F. JONES FEEDING HEAD FOR SHAKER OR JIGGING CONVEYERS 5 lSheets-Sheet 1 Filed Aug. 16, 1935 IWMSWWH NMN Jan. 26, 1937. L. F. JONES 2,068,953

FEEDING HEAD FOR SHAKER OR JIGGING CONVEYERS Filed Aug. 16, 1935 5 Sheets-Sheet 2- Ey: E

Je Je Jan. 26, 1937. L F, JONES 2,068,953

FEEDING HEAD FOR SHAKER 0R JIGGING CONVEYERS Filed Aug. 16., 1935 3 lSheel'.S-Shee1'. 5

Patented Jan. 26, 1937 UNi'iED STATES PATE cries FEEDING HEAD FOR SHAKER 0R JIGGNG CONVEYERS Application August 16, 1935, Serial No. 36,496

20 Claims.

This invention relates to improvements in feeding heads for shaker or jigging conveyers of the type used for gathering and transporting loose material such as coal, rock or the like.

More specically my invention relates to improvements in the construction of feeding heads attached to the loading end of reciprocating conveyers and has among other objects to provide a feeding head whereby extension or retraction of an extensible trough section, having a gathering shovel at the forward end thereof, is effected by reciprocating movement of the conveyer.

As heretofore constructed, feeding heads have been attached to the conveyer proper and provided with friction grip devices which are engageable with and disengageable from an extensible trough section by manual operation during certain periods of the forward or return stroke of the conveyer so as to cause the telescoping section with its shovel to be extended or retracted as required.

The manual controlling means for the grip devices have usually consisted of a system of levers arranged to shift the grip devices into an engaging or disengaging position with respect to the telescoping trough. Considerable skill is involved in the shifting of said grip devices to an engaging or disengaging position in the proper timed relation with the stroke of the conveyer, and efliciency of operation is only obtained after a great deal of experience. Furthermore, the shovel at the end of the extensible trough at times engages fixed obstructions, such as ledges in the floor or solid rock in the floor or coal seam which may under certain conditions rapidly throw the control levers in one direction or another and injure the operator if he is holding or is in the path of the operating levers at that instant.

In carrying out my invention, I provide an improved means actuated by the jigging action of the conveyer for automatically moving the cl-amping devices into engagement with or disengagement from the telescoping trough section in proper timed relation with respect to the stroke of the conveyer, whereby either feeding or retractive movement of the extensible trough will be produced without requiring special skill of the operator in manipulation of the control levers in timed relation with the stroke of the conveyer, as has heretofore usually been required in devices of this character. I also provide an improved means for gripping the extensible trough section. when the feeding-gripping devices are disconnected therefrom to permit positive (Cl. 19E-220)k feeding movement of the extensible trough section up ascending gr-ades.

Other objects of my invention will appear from time to time as the folowing specication proceeds. 5.

My invention may best be understood by reference to the accompanying drawings wherein:

Figure 1 is a side elevation of the feeding head attached to the forward end of a reciprocating conveyer with the extensible trough and digging shovel in a retracted position, and with parts of the feeding head broken away and shown in substantially longitudinal section;

Figure 2 is a top plan view of the feeding head shown in Figure l, with parts broken away and shown in substantially horizontal section in order to illustrate certain details of my invention;

Figure 3 is a sectional view taken substantially along line 3 3 of Figure 2;

Figure 4 is a sectional view taken substantially along line 4 4 of Figure 2; t Figure 5 is a sectional view taken substantially along line 5-5 of Figure 1;

Figure 6 is an enlarged detail isometric View of one of the clamping devices; 25

Figure 7 is a sectional view taken substantially along line 'l-l of Figure l; and

Figures 8, 9 10 and 11 are diagrammatic views showing the feeding mechanism in various operative positions. 30

Like reference characters refer to like parts throughout the several figures.

Referring now to the details of construction of the embodiment of my invention illustrated in the drawings, the main elements thereof consist of a reciprocating trough section IB, a feeding head ll, and an extensible trough section I2 carried by said feeding head and adapted to be nested within or extended from said trough section and having a flared gathering shovel I3 integrally carried at its forward end in the usual manner.

The feeding head includes a frame member having parallel-spaced side walls I5, I5 extending upwardly from opposite sides of a bottom plate i6. Said bottom plate is so formed that it may engage and slide along the ground when desired and is open in the central portion thereof to permit a rocking or walking shoe ld to extend therethrough and support said frame above the ground and operate my improved feeding mechanism in a manner which will hereinafter be more fully described. 'Said frame is secured to the forward end of the conveyer trough lli by means of suitable connecting bolts Il, Il registering with suitable parallel-spaced lugs I8, I8 extending inwardly from said side walls, and suitable lugs extending laterally outwardly from the forward end of said conveyer trough and disposed between the lugs I8, I8.

The means for extending or retracting the extensible trough I2 includes a pair of clamping devices 23, 23 mounted in said frame adjacent opposite sides thereof inwardly of said side plates. Each of said clamping devices is adapted to engage the upper and lower surface of one of a pair of parallel-spaced grip plates I9, I9 extending laterally from the extensible trough I2.

Each clamping device 23, as herein shown, includes an upper friction or grip block 24 adapted to engage the upper surface of said grip plate and a lower friction block 25. Said upper grip block is provided with a depending projection or tongue 20 spaced outwardly therefrom and extending within a groove 2I formed in the outer side of said lower block (see Figure 6). The sides of said groove are convexly formed to permit rocking movement of said upper grip block with respect to said lower grip block. Said tongue is slotted vertically and pivotally connected to said lower grip block by means of a suitable nut and bolt 22, extending through said slot and said lower friction block.

The lower friction blocks 25, 25 form a slidable pivotal support for the grip plates I9-, I9 and conveyer trough I2. Each of said blocks is provided with a depending tongue 21 which is adapted to slidably engage a groove 28 formed in the upper surface of a rocking member 29 (see Figures 4 and 6). Said rocking members are pivotally mounted adjacent the insides of the side Walls I5, I5 on a shaft 39 extending transversely of the frame adjacent the lower end thereof and journaled in said side walls in a usual manner. Thus, said trough may slidably move along said lower friction blocks and tilt with respect to said feeding head to engage the ground and conform to irregularities in the ground.

The upper grip block 24 is connected to the feeding head by means of a pair of spaced links 3I, 3| pivoted to the outsides of said grip block on a pivotal pin 32 (see Figures 1 and 4). Said pin has a suitable nut threaded on its outer end and a guide roller 33 journaled on the inner side thereof for engagement with the inner face of the grip plate I9 to aid in holding the extensible trough I2 in alignment with the trough section I 0 during the extending or retracting operations.

The links 3| 3I extend upwardly from opposite sides of each of said grip blocks and the free ends of each pair of said links are slidably mounted on a hand lever 34 by means of a pivotal pin 35, which is herein shown as being a bolt having a nut threaded on its outer end. Said bolt extends outwardly of said links through a collar .36 abutting the outer side of the outer link 3l.

Said collar is slidably mounted in an arcuate slot 31 formed in the side plate I5 and is slidably -mounted at its outer end in a slot 3Ia formed in and extending along the hand lever 34 to permit radial movement of said links and grip block with respect to said hand lever.

The hand levers 34, 34 are secured to the 'outer ends of the shaft 30 and form a means for properly positioning the links 3I, 3I and grip `blocks 24 and 25 for extending or retracting the extensible trough I2 as desired. A suitable locking means is provided for locking said hand levers from movement with respect to said frame which as herein shown comprises a spring-pressed pin 39 mounted in each of said hand levers adjacent the upper end thereof. Said pins are adapted to engage suitable apertures formed in the outside of the side plates I5, I5 and are so arranged that either one of them may be locked in an inoperative position, so that one only may be used, depending upon which side of the feeding head the operator is working.

The grip blocks 24, 24 are yieldably engaged with the plates I9, I9 upon either the forward or return stroke of the conveyer (depending upon the position of the hand levers 34, 34) by suitable yieldable means, which are herein shown as comprising sectors 4I, 4I. Said sectors yieldably engage rollers 38, 38 mounted between the links 3|, 3i on the bolts 35, 35. Said sectors are pivoted intermediate their ends to the insides of the side walls I5, I5 and have a concave under surface which engages said rollers. An integral lug 43 extends upwardly from the central portion of each of said sectors. Each of said lugs is adapted to be engaged by one of a pair of opposed springpressed plungers 44, 44 depending upon the position of said hand lever. Thus, when the hand lever 34 is positioned, as shown in Figure l, the blocks 24, 24 will be engaged with the plates I9, I9 upon the forward stroke of the conveyer by means of the sectors 4I, 4I, and the pins 35, 35 will move vertically in the slots Bla, 3Ia against the spring-pressed plungers 44, 44 in an obvious manner.

The clamping device 23 is moved into and out of clamping position by means of a novel arrangement of rocking devices actuated by the conveyer which includes the rocking or walking shoe i4 and a connecting link 45 pivotally connected between the bolt and said rocking shoe.

Said rocking shoe is provided with an arcuate t ground engaging surface 45 of a corrugated or non-slippable construction which has a pair of parallel-spaced legs 41, 41 extending upwardly from opposite sides thereof. Said ground engaging surface is adapted to extend through the opening in the bottom I6 of the feeding head frame for engagement with the ground and said legs are pivotally mounted at their upper ends on bolts 48, 4S mounted adjacent the upper end of said frame for vertical adjustment with respect thereto.

Said bolts extend through guided members 49, 18 which are slidable in vertically disposed guides 55, 55 formed adjacent the upper ends of the side plates I 5, I5 (see Figures l and 3). The outer ends of said bolts each have a link 5I pivotally connected thereto and extending downwardly therefrom. Each of said links has a hookedshaped lower end. Said ends are pivotally connected tothe ends of crank arms 53, 53 secured to opposite ends of a transversely extending shaft '54 so that rotation thereof will vertically move the guided members 49, 49 along the guides 5U, 5). Suitable hand cranks 55, 55 are mounted on the outer ends of the shaft 54 for pivoting said Shaft and raising or lowering said guided members with respect to the side plates i5, E5 and thus elevating or lowering said rocking shoe with respect to said frame, and permitting said shoe to support the entire feeding head above the ground.

When the crank arm 53 is in a dead center position and the hand crank extends rearwardly along the feeding head as in Figure l, the rocking shoe 46 is locked in a lowered position so that it may rest on the ground and support the entire feeding head above the ground. When in such a position, reciprocable movement of the conveyer trough lil will rock said rocking shoe about the axis of the bolts 48, 48 and reciprocably swing the gripI blocks Ztl, 24 on the free ends of the links 3l, 3l about the axis of the pivotal pins 35, 35.

In Figures l and 8, the hand levers S4, 34 and clamping devices 23, 23 are positioned to retract the extensible trough i2 and locked in such a position by means or" either one or both of the pins 39. In Figure l, the conveyor is shown at the beginning of the forward stroke. During the forward stroke the walking shoe rocks in a direction which is reverse to the direction of movement of the conveyor. This tends to move the grip blocks 24, 2li about their axes of pivotal connection to the pins 5, 35 and engages said grip blocks with the plates i9, i9 to retract the extensible tro-ugh i2 within the'trough section lo.

At this point it should be noted that upon the return stroke of the conveyor the grip blocks 2d, 24 will be moved in a forward direction by the link i5 to a disengaged position with respect to the grip plates la, i9. During such movement said grip blocks will tend to move the extensible trough section l2 in a forward direction to its initial starting point. This effect is counteracted by means of auxilia1y clamping devices l, 6l disposed forwardly of the grip blocks irl, Eli and operatively connected with the lever arms 3d, 34 so that movement of said lever arms will position said clamping devices to grip the grip plates IS, lil upon the stroke of the conveyor which is reverso from the feeding or retracting stroke. Thus, when the grip blocks 2d, 25.1 are positioned to retract the extensible trough section ii. said auxiliary clamping devices will permit said extensible trough to slide with respect to the conveyer trough lil upon the forward or feeding stroke of the conveyor and will grip said extensible trough section upon the return stroke of the conveyor. Thus, the function of said auxm iliary clamping devices is to hold said extensible trough section from movement in a direction opposite to which it is desired to feed said extensible trough section and permit a positive feeding action of said trough section. rPhe details of construction of said auxiliary clamping devices will be more fully described as this specicat'ion proceeds.

In a like manner when the hand lever 34 is locked in the position shown in'Figur-es 9 and l0 by either one or both of the locking pins 3S, they grip blocks 2li, 2t will be positioned to engage the grip plates i9, i upon the return stroke of the conveyer and the auxiliary clamping devices 62, 8l will be positioned to engage said grip plates upon the forward stroke of the conveyor to permit said grip blocks to extend said extensible trough from the trough section I@ and feed the shovel i3 into the material it is desired to pick up.

When it is desired to render the feeding mechanism inoperative during reciprocation of the conveyor, the hand crank 55 is moved 180 in a counter-clockwise direction to the position shown by solid lines in Figure il, which elevatcs the rocking shoe iii above the ground in an obvious manner and locks said shoe in such a position due to the fact that the position of the crank 53 with respect to the link 5l past dead center.

The clamping devices 23, E13 are locked in an engaged position with respect to the gripping plates i9, i9 when the hand levers 34, 35i and grip blocks 24, 2t are positioned to extend the extensible trough i2, and the shoe I4 is elevated above the ground by suitable locking means which includes a lug 59 extending upwardly from each leg 4i of the rocking shoe 46. Said lugs each have an inclined lupper face which is inclined upwardly toward the rearward end thereof. Said faces are adapted to be engaged by corresponding inclined faces of inwardly extending projections t, d@ depending downwardly from and spaced inwardly of the upper sides of the side plates i5, i5. Thus, when the rocking shoe ifi is disengaged from the ground, the inclined faces of the lugs 59, 59 will engage the inclined faces of the projections 6i), Ell. This will position said rocln'ng shoe in the forwardly extended position shown in Figure l1. Said shoe will be held in such a position by the link 5l and crank 53 which is past a dead center position. When said rocking shoe is so locked, the clamping devices 23, 23 are held in engagement with the plates it, lil when said clamping devices are positioned to extend said extensible trough section in the manner previously described. When it is desired that the trough sections be freely movable with respect to each other, and said shoe is disengaged from the ground, the hand levers tti, Sii are moved to the position shown in Figure l to disengage said blocks from said plates.

The auxiliary clamping devices, 6l, 6l ale mounted on the side Walls l5, i5 and extend forwardly therefrom. Said clamping devices are adapted to engage the grip plates i9, I9 when the clamping devices 23, 23 are disengaged therefrom in order to insure proper feeding, especially when extending the shovel along ascending grades. Said clamping devices are also adapted to engage said grip plates upon the stroke of the conveyer which is the reverse stroke from the feeding or retracting stroke, depending upon the position of the hand levers 34, 34, to hold the extensible trough section from movement with respect to the conveyer trough section in the manner previously described. As herein shown, said auxiliary clamping devices each include an upper grip block 62 and a lower grip block 63 mounted on a carrier' member 64 (see Figures l and 5). The grip blocks 62 and are pivotally mounted on said carrier member on suitable pivotal pins 65 and ii, respectively, which are herein shown as being bolts having nuts threaded on the ends thereof. A bifurcated end of a connecting link 6l is pivotally connected to the pin tia on opposite sides of the lower grip block @3. Said connecting link extends rearwardly from said grip block and is pivotally connected to the side plate i5 on a pivotal pin tit. In a like manner, a bifurcated end of a connecting link 69 is pivotally connected to` the pin t5 on'opposite sides of the upper grip block ttl. Said link extends rearwardly from said grip block and is pivotally connected to the upper end of a rocking arm it. Said rocking arm is pivotally connected intermediate its ends to the side plate l5 on the pivotal pin 68. The lower end of said rocking arm has a link 'il pivotally connected thereto and extending rearwardly therefrom to a projection 12 extending inwardly from the hand lever 34 adjacent the lower end thereof through a suitable opening in the side plate l5.

The lower end of the carrier member 64 has a roller i3 mounted thereon. Said roller is adapted to react against one slope or the other of a peak 'I4 formed on the forward end of a lever arm l5, depending upon the operative position of the hand lever 34. Said lever arm is pivoted to the side plate I5 for movement about an axis extending transversely thereof and the peaked end of said lever arm is yieldably engaged with said roller by means of a compression spring 'IS in the usual manner.

Referring now to the operation of the auxiliary clamping devices 6|, 6I, it will be understood that they work automatically in conjunction with the clamping devices 23, 23 to enable said second-mentioned clamping devices to produce a positive feeding action to the shovel, even when working on ascending grades.

It will be seen by reference to Figures 1 and 8 that when the extensible trough I2 is being retracted within the trough section I0 that the roller I3 is engaged with the rearward slope of the peak 14. When in such a position, the grip blocks 62 and 63 are engaged with the plates I9, I9 by means of the compression springs 1B, 76. Thus, when the trough I2 is retracted by the clamping devices 23, 23, the carrier 64 is pivoted in a rearward direction about its axis of pivotal connection to the link 61, and the grip blocks 62 and 63 are released from the plates I9, I9. When the conveyer commences its forward stroke, said grip blocks are engaged with said plates by means of the springs I6, 'I6 and hold said trough from forward movement with respect to said feeding head.

In a like manner, when the hand lever 34 is positioned to extend the trough section I2 from the trough section I0, as is shown in Figures 9 and 10, the roller 'I3 is engaged with the forward slope of the peak 'I4 and the grip blocks 62 and 63 hold the trough section I2 from rearward movement with respect to said feeder head.

It should herein be noted that the gripping force of the grip blocks 62 and 63 is determined by the tension of the spring 'I6 and that said grip blocks may automatically release themselves when pressures on the extensible trough are excessive.

It will thus be apparent that a new and improved feeding mechanism has been provided for shaker conveyers wherein an extensible trough and shovel may be fed into the material it is desired to load by the action of the conveyer itself, and that this device is so arranged as to be automatically operable and manually adjustable in such a manner that when it is once set in the proper position feeding will continue until the end of the extensible trough section is reached. It should also be apparent that while the auxiliary clamping devices 6I, 6I serve to prevent movement of the extensible trough section with respect to the conveyer trough section when the clamping devices 23, 23 are disengaged therefrom and upon the stroke of the conveyer opposite from the feeding or retracting stroke, depending upon the position of the hand levers 34, 34, that said auxiliary clamping devices also enable the improved form of feeding device to be efficiently utilized for loading along ascending grades or pitching seams in that they prevent backward slipping movement of the extensible trough section with respect to the conveyer trough section.

While I have herein shown and described one form in which my invention may be embodied, it will be understood that the construction and arrangement of the various parts may be changed or altered Without departing from the spirit or scope thereof. Furthermore, I do not wish to be construed as limiting myself to the precise construction illustrated, excepting as it may be limited in the appended claims.

I claim as my invention:

l. In a feeding head for a jigging conveyer and in combination with an extensible trough, a clamping device carried by said head, and means operated by said shaker conveyer for moving said clamping device in and out of clamping position relative to said extensible trough comprising a rocking member engageabie with the ground and rocked by reciprocable movement of said conveyer, and an operative connection between said rocking member and clamping device.

2. In a feeding head for a jigging conveyer and in combination with an extensible trough, a clamping device carried by said head, and means operated by said shaker conveyer for moving said clamping device in and out of clamping position relative to said extensible trough comprising a rocking member engageabie with the ground and adapted to support said feeding head above the ground, and an operative connection between said rocking member and clamping device.

3. In a feeding head for shaker conveyers, a shaker conveyer pan line having said feeding head secured to the forward end thereof, an extensible trough carried by said feeding head, a clamping device carried by said feeding head, and means for moving said clamping device in and out of clamping position relative to said extensible trough comprising a rocking member pivoted to said feeding head and engageable with the ground, and an operative connection from said rocking member to said clamping device.

4. A feeding head in accordance with claim 3, wherein the rocking member is adapted to support the feeding head above the ground.

5. A feeding head in accordance with claim 3, wherein the rocking member is adapted to support the feeding head above the ground and wherein the feeding head is vertically adjustable with respect to the rocking member to permit said feeding head to rest on the ground.

6. In a reciprocating conveyer, a reciprocating trough section, an extensible trough adapted to be nested therein or extended therefrom. and

means operated by reciprocable movement of said conveyer for extending said extensible trough from said trough section or retracting said trough within said trough section comprising a clamping device adapted to engage said extensible trough upon movement of said reciprol eating trough in one direction and be disengaged from said extensible trough upon reverse movement of said reciprocating trough, and means for moving said clamping device in and out of clamping position relative to said extensible trough comprising a rocking shoe adapted to engage the ground and an operative connection between said rocking shoe and clamping device.

'7. In a reciprocating conveyer, a reciprocating trough section, an extensible trough adapted to be nested therein or extended therefrom, and means operated by reciprocable movement of said conveyer for extending said extensible trough from said trough section or reti-acting said trough within said trough section comprising a frame secured to and extending forwardly from said reciprocating trough section, a clamping device pivoted to said frame, and means for moving said clamping device into and out of clamping position relative to said extensible trough comprising a rocking shoe pivoted to said frame at a point disposed above said trough section and having supporting engagement with the ground, and an operative connection between said rocking shoe and clamping device.

8. A reciprocating conveyer in accordance with claim 7 wherein said frame is supported on said rocking shoe during extension or retraction of said trough and wherein means are provided to adjustably move said frame relative to said shoe and permit said frame to rest on the ground.

9. In a reciprocating conveyer, a reciprocating trough section, an extensible trough adapted to be nested therein or extended therefrom, and means operated by reciprocaole movement of said conveyer for extending said extensible trough from said trough section or retracting said trough within said trough section comprising a frame secured to and extending forwardly from said reciprocating trough section, a clamping device including a pair of grip blocks adapted to engage upper and lower portions of said extensible trough section, a link pivotally connected to one of said grip blocks and having pivotal connection with said frame, a rocking shoe pivoted to said frame, said shoe being adapted to engage the ground and rock upon reciprocating movement of said reciprocating trough section, and an operative connection between said rocking shoe and grip blocks.

l0. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to said feeding head a connection from the opposite end of said link to said lever arm intermediate the ends thereof, and means for moving said clamping device into and out of clamping engagement with said conveyer trough comprising a rocking member engageable with the ground and actuated by reciprocable movement of said shaker conveyer.

1l. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to said feeding head, a connection from the opposite end of said link to said lever arm intermediate the ends thereof, and means for moving said clamping device into and out of clamping engagement with said conveyer trough comprising a rocking member adapted to have supporting engagement with the ground and support said feeder head above the ground during extension or retraction of Said extensible trough.

l2. A feeding head in accordance with claim il, wherein the rocking member is supported on the feeding head and wherein means are provided for vertically adjusting the rocking member with respect to the feeding head to permit said feeding head to rest on the ground and disengage said rocking member from the ground.

13. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends a lever arm pivoted to said feeding head, a connection from the opposite end of said link to said lever arm, another clamping device adapted to engage said extensible trough when said first-mentioned clamping device is disengaged therefrom and upon the stroke of the conveyer opposite from the feeding stroke, a connection from said last-mentioned clamping device to said feeding head including a rocking member pivoted to said feeding head, and a connection from said rocking member to said lever arm, and means for moving said first-mentioned clamping device into and out of clamping engagement with said conveyer trough comprising a rocking member having a rocking surface adapted to engage the ground.

14. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to said feeding head, a connection from the opposite end of said link to said lever arm, another clamping device adapted to engage said extensible trough when said first-mentioned clamping device is disengaged therefrom and upon the stroke of the conveyer opposite from the feeding stroke, a connection from said last-mentioned clamping device to said feeding head including a rocking member pivoted thereto, a rocking member pivoted to said feeding head intermediate its ends a connection from one end of said rocking member to said clamping device and a connection from the opposite end of said rocking member to said lever arm, and means for moving said first-mentioned clamping device into and out of clamping engagement with said conveyer trough comprising a rocking member having a rocking surface adapted to engage the ground.

l5. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to said feeding head, a connection from the opposite end of said link to said lever arm intermediate the ends thereof and means for moving said clamping device into and out of clamping engagement with said conveyer trough comprising a rocking member adapted to engage the ground and actuated by reciprocable movement of said shaker conveyer, and a link connecting said rocking member with said clamping device.

16. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to saidfeeding head, a connection from the opposite end of said link to said lever arrn intermediate the ends thereof, and means for moving said clamping device into and out of clamping engagement With said conveyer trough comprising a rocking member adapted to engage the ground and actuated by reciprocable movement of said shaker conveyer, and a link connecting said rocking member with said clamping device at the point of connection of said first-mentioned link thereto.

17. In a shaker conveyer, a feeding head therefor, an extensible trough guided for horizontal movement relative to said head, a clamping device adapted to engage said extensible trough including a pair of opposed grip blocks adapted to have clamping engagement with said trough, means for positioning said clamping device for feeding said extensible trough in either a forward or rearward direction relative to said head including a link pivoted to said clamping device at one of its ends, a lever arm pivoted to said feeding head, a connection from the opposite end of said link to said lever arm intermediate the ends thereof, and means for moving said clamping device into and out of clamping engagement with said conveyer trough comprising a. rocking member adapted to engage the ground and actuated by reciprocable movement of said shaker conveyer, and means for holding said extensible trough from movement with respect to said head when said clamping device is disengaged therefrom and upon the stroke of the conveyer opposite from the feeding stroke comprising another clamping device pivotally connected to said feeder head and having connection with said firstmentioned lever arm.

18. In a feeding head for shaker conveyers, a shaker conveyer pan line having said feeding head secured to the forward end thereof, an extensible trough carried by said feeding head, a clamping device carried by said feeding head, means for moving said clamping device in and out of clamping position relative to said extensible trough comprising a rocking member pivoted to said feeding head and engageable with the ground and an operative connection from said rocking member to said clamping device, and means for holding said extensible trough from movement with respect to said feeding head when said clamping device is disengaged from said extensible trough and upon the stroke of the conveyer opposite from the feeding stroke comprising another clamping device extending forwardly of and having pivotal connection with said feeding head.

19. In a feeding head for shaker conveyers and in combination with an extensible conveyer trough section, a clamping device carried by said feeding head and adapted to be moved into and f movement of said conveyer, a connection from n said rocking member to said clamping device for moving said clamping device into and out of clamping engagement with said trough section, and another clamping device for engaging said trough section upon the stroke of said conveyer opposite from the feeding stroke.

20. In a feeding head for shaker conveyers and in combination With an extensible conveyer trough section, a clamping device carried by said feeding head and adapted to be moved into and out of clamping engagement with said trough section for moving said trough section relative to said feeding head, a rocking member engageable with the ground and rocked by reciprocable movement of said conveyer, a connection from said rocking member to said clamping device for moving said clamping device into and out of clamping engagement with said trough section, means for positioning said clamping device to extend or retract said extensible trough with respect to said feeding head, another clamping device for engaging said trough section upon the stroke of said conveyer opposite from the feeding stroke, and an operative connection from said secondmentioned clamping device to said positioning mea/HS.

LOUIS F. JONES. 

